Some conventional pieces of luggage, such as carry-on suitcases and rolling duffel bags, may have rollers on the bottom to make the bags easier for travelers to transport. However, travelers often need to transport two or more wheeled pieces of luggage simultaneously. If a traveler needs to transport two wheeled pieces of luggage, both hands are typically required. Consequently, while transporting two or more large, heavy pieces of luggage, the traveler may find it difficult or impossible to do other things, such as answering a cellular telephone call, retrieving cash or keys from a pocket or purse, holding the hand of a small child, etc.
Furthermore, in many situations, travelers find it difficult to maneuver multiple pieces of luggage simultaneously. For instance, it can be difficult to safely transport two large pieces up or down a step or escalator, or to transport both pieces through a narrow opening. Such maneuvers may be particularly difficult when the traveler is small and one or both of the pieces of luggage are large and heavy. When more than two pieces need to be transported, these kinds of difficulties may be multiplied.